Governor mechanism



H. K. SANDELL.

' GOVERNOR MECHANISM.

AP. 5, l8, 1,329,800, Patented Feb. 3,1920.

2 $HEETSSHEET I.

H. K. SANDELL.

GOVERNOR MECHANISM.

APPUCATION FILED APR. 5. I918.

Patented Feb. 3,1920.

2 SHEETSSHEET 2- ////A m i WWI/11W UNITED STATES PATENT OFFICE.

HENRY K. SANDELL, OF CHICAGO, ILLINOIS, ASSIGNOR TO'HERBERT S. MILLS, OF

CHICAGO, ILLINOIS.

GOVERNOR lVIECI-IANISM.

Application filed April 5, 1918.

To all whom it may concern:

Be it known that I, HENRY K. SANDELL, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a new and useful Improvement in Governor Mechanism, of which the following is a specification.

My invention relates to improvements in governor mechanisms, and more particularly to such mechanisms adapted for use in phonographs, and will be fully understood from the following description taken in connection with the accompanying drawings in which Figure 1 is a bottom plan view of a phonograph table constructed in. accordance with my invention. Fig. 2 is a transverse section on the line 2-2 of Fig. 1. Fig. 3 is a detail section. of the governor taken on the line 3-3 of Fig. 1; and Figs. l and are additional details of the governor taken, respectively, on the lines l-4 and 5-5 of Fig. 1.

Referring more particularly to the drawings, the numeral designates an annular frame having oppositely-disposed segmentalenlargements 11 which carry the motor windings and the governor mechanism.

- This frame is adapted to be mounted within an aperture in the top of the cabinet 12 of the phonograph to support the table motor and governing mechanism as a complete unit. On its lower face the frame 10 carries a bridge piece 13 which supports a verticallybored boss 14:, the latter forming a bearingsupporting-member for the vertical table shaft 15. This shaft is carried by a self-centering ball thrust bearing 16 at its upper end and is guided at its lower end by a bushing 17. Intermediate its ends the table shaft is secured against longitudinal displacement by a screw 18, the reduced point of which bears within a groove 19 turned in the shaft.

The phonograph table 20, which is of the usual disk-like form on its upper surface, is mounted on the shaft and carries a plurality of depending lugs 21 which are preferably of considerable weight and cast integrally with the table. These lugs are shouldered intermediate their length, and to the shoulders there is secured the field ring 22, of the table motor.

'For cooperating withthe rotating held there is provided stationary segmental armature, the core 26 of which is fastened Specification of Letters Patent.

Patented Feb. 3, 1920.

Serial No. 226,804.

to the lower face of one of the segmental enlargements 11 of the frame.

The motor provided for operating the record table is a self-starting single phase induction motor having a rotating field and stationary windings, and is capable of operating efiiciently through a wide range of speed.

The lower ends ofthe lugs 21 carry an annular plate cam which is bent to an approximately sinusoidal curve and is fastened to the lugs by cap screws which confine the cam between vibration-absorbing washers 36 preferably formed of leather, fabric or rubber. The sinusoidal plate cam 35 constitutes the governor actuating mechanism. For cooperation therewith I provide a governor of the general nature of a balance wheel escapement. The governor mechanism is supported on a depending arm 87 carried by the frame 10 and in turn supporting a horizontal shaft 38. Upon this shaft there is mounted a balance wheel 39, the hub of which has for a bearing a felt bushing 4:0. Beyond the balance wheel 39 there is journaled on the shaft 38 a sleeve 41, the outer end of which carries a fork l2 which straddles the edge of the cam plate. The ends of the fork have seciilred thereto relatively stiff transverse springs 43, the springs carrying at their ends felt contact blocks a l which bear lightly upon the faces of the disk, as is shown in Fig. The distance between the contact points of the blocks 44 at opposite ends of the springs 13 approximately equal to onehalf the wave length of the cam 35. The fork-carrying sleeve 41 is connected with the balance wheel 39 by a spiral spring 45, the inner end of which is secured to the sleeve l1, in the plane of the spring, while the outer end is turned rearwardly to engage a spoke of the balance wheel, being secured thereto by a rivet as shownat 46. The sleeve 41, like the balance wheel 39, has a felt bushing which serves as a hearing. The governor shaft assembly is completed by thrust washers 17 which retain the parts in their proper spaced relationship. these washers also being conveniently made of felt.

For adjusting the period of vibration of the governor balance wheel, there provided an additional spring in the form ofa tension coil 48 caught at one end in the wheel and at the other end secured to a lever 49 pivoted to a lug on the lower face of the frame. A quick-acting adjustment is pro- Vided in the form of a snail cam 50, the cam surface of which acts upon the lever t9, the cam being in turn actuated through a shaft by a thumb wheel 51 on the top of the frame.

The governor mechanism described operates in the following manner. As the table 20 carrying the sinusoidal cam plate 35 revolves, the sleeve 41-1 is oscillated by the contact of the felt blocks 4% with the wavy surfaces. By this oscillation the balance wheel 89 is synchronously oscillated through the spiral spring 45. If the speed of the table is such as to give an oscillation frequency corresponding to the natural frequency of the balance wheel, as determined by the form and mass of the latter and by the force of the spring, the contact felts Mt follow the curves of the cam plate with very little resistance. If, however, the speed of the table tends to exceed this critical value, the oscillations of the balance wheel will no longer synchronize with the oscillations of the sleeve 41, and, as a result, a conside "able pressure will be exerted upon the felt contact blocks la causing the latter to act as brakes for retarding the table, thus tending to hold the latter down to a certain definite speed fixed by the periodicity of the balance wheel.

The operation of my improved phonograph motor as a whole is as follows:

The motor being connected to a service line of the proper potential a torque is exerted upon the rotating field and the table thereby set in motion. This starting torque of the motor is particularly high and is effective to bring the table up to speed within a relatively short period. In its initial acceleration the table is, of course, out of synchronism with the balance wheel of the governor and the latter, therefore, exerts some retarding effect, but due to the lower velocity of the table this retardation is not sufiicient to overcome the forward torque of the motor. The latter therefore comes up to the synchronous speed determined by the periodicity of the balance wheel, and, in fact, slightly exceeds this speed until the braking effect of the contact blocks 44.- halances the surplus torque of the motor. The table is now in normal operation at its governed speed. The designed load, such, for example, as the record and the reproducer needle bearing thereon, may now be applied without appreciably altering the speed of the table. In fact, I have found by tests that the variation in speed of the table, with a load varying through a range several times as great as that met by the phonegraph in practice, will not cause any change in speed which may be detected without the aid of instruments. This extreme accuracy of regulation I attribute primarily to the Leeaeoo on mechanisms.

Control of the speed of revolution of the table is obtained by single ad ust1nent, z. 6.,

the thumb-sci w 51, which regulates the tension of the spring 4:8 and thereby varies the na al frequency of the balance wheel. By movement of less than one revolution of this thumb-wheel the speed of the phonograph table may be changed through the widest range required in this service.

While I have in the foregoing described in considerable detail one specific construc tion in accordance with my invention, it will be understood tha this is illustrative only and for the purpose of making the invention more clear, and that the invention is not to be regarded as limited to any of these details, except in so far as the same are included within the terms of the appended claims in which it is my intention to claim all novelty inherent in my invention as broadly is permissible in view of the prior art.

What 1 claim isl. The combination with a continuously rotating driven member of a serpentine c'am carried thereby, an oscillatory resilient cam follower cooperating with the cam, and an oscillating balance wheel connected with the cam follower.

2. The combination with a continuously rotating driven member of a serpentine cam carried thereby, an oscillating resilient cam follower cooperating with the cam, an oscillating balance wheel, and spring connections between the balance wheel and cam follower for driving the former from the latter.

3. The combination with a phonograph table of a cam coincidently driven therewith, and a balance wheel mechanismoperable from the said cam.

l. The combination with a phonograph table of a cam driven thereby, an oscillatory cam follower cooperating with the cam, an oscillatory balance wheel, and spring connections between the cam follower and the balance wheel.

5. The combination with a phonograph table of a serpentine cam carried thereby, an oscillatory cam follower operable by the said cam, and abalance wheel mechanism connected with thesaid cam follower.

6. The combination with a phonograph table of a serpentine cai carried thereby, an oscillatory cam follower cooperating with the said cam, balance wheel mounted co-axially with the cam follower and spring connections between the cam follower and balance wheel. 7

7. The combination with a phonograph table of a serpentine cam carried thereby. an oscillatory cam follower cooperating with the cam, a balance wheel arranged co axially with the said cam follower, means for Varying the periodic time of the said balance Wheel and spring connections between the cam follower and the balance Wheel for driving the latter from the former.

8. The combination with a phonographtable of a serpentine cam carried thereby, an oscillatory fork straddling the said cam, spaced opposed cam follower-points carried by the prongs of the said fork, the spaces between the said points being equal to one-half the Wave length of the said serpentine cam, and a balance Wheel mechanism driven by the said oscillatory fork.

9. The combination With a phonograph table of a serpentine cam carried thereby,

an oscillatory fork stradding the said cam,

spaced opposed cam follower-points carried by the prongs of the said fork, the spaces between the said points being equal to onehalf the Wave length of the said serpentine cam, a balance Wheel mechanism, and spring connections for driving the same from the said fork.

HENRY K. SANDELL. 

